While riding yesterday I noticed the lock ring, that holds the rotor in place, came loose on my front wheel. I have little mechanical knowledge about bikes so wondered if someone can give me some advice?
How do you tighten up the lock ring?
At the moment I have just used my fingers to get it as tight as I can. Should I be using a special tool?
I have noticed some very, very slight movement in the front wheel when front brake is applied and I rock bike back and forward. Could this be the reason for the lock ring working loose? Thanks for any help.
How do you tighten up the lock ring?
It's just a cassette lockring tool. [url= http://www.halfords.com/cycling/tools-maintenance/tools/bikehut-professional-cassette-tool ]Halfords sell them[/url] if you need something local, or [url= http://www.chainreactioncycles.com/park-tool-cassette-lockring-tool-fr5/rp-prod7213 ]CRC do one if you're going mail order[/url].
...or just see if your LBS has one.
You will need a wrench to tighten it, tho.
Should I be using a special tool?
Yes. Although it's not really special.
At the moment I have just used my fingers to get it as tight as I can
I would strongly recommend popping into your LBS, and get them to nip it up for you, while you source a tool.
I have noticed some very, very slight movement in the front wheel when front brake is applied and I rock bike back and forward. Could this be the reason for the lock ring working loose? Thanks for any help.
Hard to say while you have a loose lockring. Get that tightened up, and then see if you still have any movement.
.
It most definitely cannot be tightened (adequately) by hand. It needs to be really tight to prevent it loosening from rocking on the splines.
External BB tool if a 15 mm axle hub, or a cassette locking tool if a QR hub.
Riding it with a finger tight locking would be mental.
Came back to edit, but as per sillyoldman, if you have a 15mm front axle, rather than a QR hub, then you would need a bb spanner [url= http://www.chainreactioncycles.com/cyclo-hollowtech-ii-bottom-bracket-tool/rp-prod42809 ]like this.[/url]:
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Thanks for advice, only rode finger tight to get back to car, so not fully mental yet, though many who know me would probably disagree!
It's a QR hub.
Mental bit was aimed at jamiep who swiftly edited his less than sage advice.
It's a QR hub.
Then as per my first post.
This seems a decent priced all-in-one tool if you wanted to go that route:
http://www.wiggle.co.uk/bbb-btl-12-lockout-lock-ring-removal-tool/
OP, if you just want your front one tightening up, any casette tool will be fine. however if you have centerlok rotor on your back wheel too then at some point you might want to get a 'deep cup' cassette tool, as the normal size one will not clear the axle/locknuts on the disc side of your rear hub to engage with the rotor lockring. Superstar do a cheap one which is fine and of course works fine on cassettes too, there is a proper shimano one too that looks nicer but more spendy.
